sudo choco install python2 -y -o -ia "'/qn /norestart ALLUSERS=1 TARGETDIR=c:\Python27'"
yarn config set python "C:\Python27\python.exe"
$env:PY_HOME = "C:\Python27"
$env:Path = "C:\Python27;" + $env:Path
yarn
if it doesnt work, change the env manually, and then revert it after install completed.